8. Genes

A full length cDNA sequence…

1) contains no 5’ UTR

2) contains no 3’ UTR

3) is the sequence of the unspliced RNA transcript

4) is the complete cDNA sequence of a transcript including the 5’ and 3’ UTR regions -> correct

5) is a manually annotated reference gene sequence

Which statements about cDNA libraries are true?

1) If a cDNA library is sequenced with primers located in the plasmid, the generated sequences are called ESTs -> correct

2) Full length cDNAs usually can be sequenced with two reads

3) A human cDNA library usually contains sequences from >90% of all human genes

4) Most cDNA clones contain the full mRNA sequence

5) For most human genes only one cDNA is known

Which statements about databases relevant for Genomics are true?

1) GenBank, DOBJ and EMBL contain essentially the same information since they exchange data on a daily basis -> correct

2) GenBank contains only human sequences

3) Each GenBank entry has a unique identifier -> correct

4) RefSeq is a genome Browser

5) ENSEMBL provides important Gene builds for many genomes -> correct

Which statements regarding the number of (protein-coding) genes in the human genome are true?

1) Humans have the most genes among all mammals

2) In vertebrates the number of genes correlates well with genome size

3) There are several bacteria known that have more genes than humans

4) Plant genomes can contain more genes than the human genome -> correct

5) The chicken has ~twice as many protein coding genes as humans

Which statement regarding the annotation of (human) genes is correct?

1) Ensembl contains the manual “Havana” gene annotation for human, mouse, rat, pig and zebrafish -> correct

2) The automatic gene annotation of Ensembl is based on experimentally obtained data such as cDNA sequences -> correct

3) CCDS transcripts only cover the coding part of transcripts -> correct

4) BioMart is a web portal to access Ensembl gene annotations -> correct

5) Each annotated human protein coding gene in Ensembl has by defintion be confirmed by Mass spectrometry or other technologies that prove the presense of this protein

Which statement regarding splicing in human protein coding genes are true?

1) The splice donor site is located in the exon -> wrong, in the intron

2) Alternative splicing affects most genes -> correct

3) When aligning a cDNA sequence to the genome, the polyA tail does not align -> correct

4) Alternative splicing can also affect the 5’UTR -> correct

5) Usage of alternative 5’ donor sites can lead to alternative splicing -> correct

Which statements regarding non-coding RNAs (ncRNAs) are correct?

1) piRNAs are involved in transposon control -> correct

2) XIST is a micro RNA

3) Most ncRNAs are expressed at lower levels than protein-coding RNAs -> correct

4) For the vast majority of ncRNAs a biological function has been shown

5) Most ncRNAs found in a population of cells are present in fewer than one copy per cell -> correct